Retractable cutter head support



Oct. 1, 1963 Filed Sept. 11, 1961 T. 0. BROWN 3,105,677

RETRACTABLE CUTTER HEAD SUPPORT 2 Sheets-Sheet l lNVENTORI THOMAS OWEN BROWN ATTO R NEY 0a. 1, 1963 T. 0. BROWN 3,105,677

RETRACTABLE CUTTER HEAD SUPPORT Filed Sept. 11, 1.961 2 Sheets-Sheet 2 INVENTORZ THOMAS OWEN BROWN ATTORNEY United States Patent 3,105,677 RETRAQTABLE CUTTER HEAD SUPPORT Thomas 0. Brown, Bridgeport, W. Va, assignor to Charies E. Compton, Clarirshurg, W. Va. Filed Sept. 11, 1961, Ser. No. 137,250 3 Claims. (Cl. 262-9) This invention relates to a retractable cutter head and more particularly to the means for positioning and maintaining the cutter head in operative position relative to its supporting structure.

In boring type mining machines which cut adjacent bores in a seam of coal or the like, it is customary to provide auxiliary cutting heads adjacent the boring heads to aid in the cutting of the main seam as well as to cut clearance space at the roof and floor levels and outwardly of the lower side portions of the machine. In addition to the lower auxiliary cutting heads such boring machines usually have an orbital moving chain guided for movement in a grooved track along the lower transversely extending forward portion of the boring machines. It is desirable to provide means for laterally extending and retracting the boring heads as well as the lower auxiliary cutting heads to provide clearance space for maneuvering the machine into various operating positions as well as providing the necessary clearance space for retracting the entire machine from the cut bore.

The lower auxiliary cutter means are generally pivotally mounted on the forward lower end portions of the main frame and operable to produce the above mentioned clearance space for the lower side portions of the machine.

In the past it has been the practice to operate the pivotal'lower auxiliary cutting heads or extension means by hydraulic jacks or by links in conjunction with a hydraulic jack to form a column to resist the forces tending to retract the retracting extension means. However, such hydraulic jacks often tend to buckle while in use and damage the jack or its connections. The present invention employs locating means which cooperates with the hydraulic jack for positioning and independently maintaining the lower auxiliary cutter head in its outermost working position for cutting without reliance upon the hydraulic jack. Additionally the locating means upon actuation by the jack retracts the auxiliary cutter head into its retracted position wherein the auxiliary cutter head is completely withdrawn from the lateral cut sides of the mine passageway to provide sulficient clearance space for maneuvering and the withdrawal of the mining machine as aforementioned. The principal object of this invention is to provide a new and improved adjustable auxiliary cutter head which cooperates with a cutter chain for movement laterally into cutting position and firmly held therein.

A further object of this invention is to provide power operated means cooperable with locating means for a cutter head which positively maintains the cutter head in its cutting position without reliance on a hydraulic jack.

Other objects and advantages of the present invention will more fully appear as the following description proceeds.

In the drawings:

FIG. 1 is a side elevational View of the forward portion of a mining machine which employs the lower auxiliary cutting head and cutter chain in accordance with the principles of this invention;

FIG. 2 is a front elevational view of the mining machine showing the relationship of the forward boring heads to the lower auxiliary cutting heads and a chain assembly wherein the auxiliary cutting heads are in laterally extended positions;

FIG. 3 is an enlarged front elevational view of a sup- 3,1d5,d7i7 Patented Oct. 1, 1963 port plate to which a motor for one of the auxiliary cutting heads is to be secured;

FIG. 4 is a side elevational view of the support plate and the support bracket of the motor and the auxiliary cutting head;

FIG. 5 is a rear elevational view of the support bracket for the motor and the auxiliary cutting head with the retracting and position maintaining means thereof.

The improved mining apparatus, as shown in the drawings, generally comprises a frame or support structure 2 suitably mounted on a mobile base 1 about which conventional endless crawler treads 8 are guided for orbital circulation. The main frame 2 is adjustably supported on the mobile base 1.

A scraper blade head 20 (FIG. 2) is suitably rigidly secured to the forward lower portion of the main frame 2 upon which material is loaded through the forward propulsion of the mobile base 1. A longitudinal center portion of the main frame 2 provides the deck over which a conveyor extends for cooperation therewith to convey coal or mined material from the forward edge portion of the blade head 20 onto the conveyor in a manner clearly understood and well known in the art.

A pair of adjacent laterally spaced cutter head assemblim 40 located on the forward end of the main frame 2 are suitably rotatably mounted on shafts which extend respectively from a transmission housing 42, which housings 42 are located on respective laterally extending guide frames of the main frame 2. To provide additional guide means for each transmission housing 42 a yoke 28 is suitably secured to the forward portion thereof with the lower bottom end portion of the yoke: 28 being slidably received between a pair of parallel spaced guideways 29 suitably secured to a laterally extending bracket 34 on the main frame 2. Each cutter head assembly 4% is arranged to cut a pair of parallel bores in the seam of coal or mineral, and leaves a generally circumferential wall or rib at the. sides of the machine. Such boring action also leaves upstanding cusps on the floor which are cut off by a chain 6t) suitably mounted for movement on scraper blade head 20.

The scraper blade head 2% suitably supports the endless cutter chain of which chain 60, in the forms shown in FIG. 1 and FIG. 2, travels from left to right along scraper head 26, thence around a driven corner sprocket 35 mounted on an auxiliary cutting head 10 to be described, upwardly and thence inwardly to an idler sprocket 96 which is suitably mounted on the central portion of frame 2 of the mining apparatus, then downwardly to a second driven corn-er sprocket on another auxiliary cutting head 10 similar to the previous one referred to thence back to the scraper blade head 29. The respective corner sprockets 95 and the respective auxiliary cutting heads are movable with their respective extension means, as will presently be described.

Referring to FIGS. 3, 4 and 5 only one mounting means for an auxiliary cutting head 1% and its respective driven sprocket 95 will be described; however, it will be understood that :the mounting means for each auxiliary cutting head are the same. For convenience, the lower righthand auxiliary cutting head or extension means will be described since both extension means are essentially similar.

An elongated fiat support bracket 82 has one end pivotally mounted on a shaft 81 that is journaled on the lower side of main frame 2 where-in the axis of shaft 81 is parallel to the longitudinal center line of the machine. The central portion of bracket 82 near pivot shaft 81, is suitably arcuately slotted as at 90, which arcuate slot 9% is generally on a radius swung from the axis of shaft 81. Journaled on frame 2 and extending through arcuate slot 90 is a shaft 33 which engages the upper end of slot 90 when bracket 82 is in its lowermost position. Shaft 88 limits the pivotal movement of support bracket 82 about pivot shaft 81, such that the clockwise movement (as viewed in FIG. of bracket 82 about pivot shaft 81 is limited by the bottom end of the arcuate slot 90 engaging shaft 88 and the counterclockwise movement is limited by the upper end of arcuate slot 96). Thus the movement of support bracket 82 about pivot shaft 81 is determined by the length of slot 90. When support bracket 82 has the upper end of slot 99 resting on shaft 88, the lower bottom surface of support bracket 82 is substantially horizontal and in engagement with the mine floor whereas when the bottom end of arcuate slot 90 engages shaft 88 the support bracket 82 is in its withdrawn or raised position.

A lever arm 84 has its lowermost end pivotally connected by a shaft 85 to the lower intermediate portion of support bracket 82 and its upper end portion pivotally connected by a shaft 87 to the lower edge of a triangular flat disk 86, which disk 86 has its apex edge pivotally mounted to the shaft 88, which shaft 88 as previously described is journaled on the main frame 2. Thus shaft 88 is the pivotal axis for disk 86 while permitting the pivotal movement of support bracket 82 by means of arcuate slot 9-0 on pivot shaft 81. The remaining outward edge of the triangular disk 86 is pivotally connected to a rod end of a hydraulic jack 92 with the cylinder end of the hydraulic jack 92 being pivota-lly connected to the frame 2 on a shaft 89, which shaft 89 is located vertically above the shaft 81.

Spaced longitudinally forwardly from the elongated support bracket 82 and pivotally mounted on support shaft 81 is a generally flat elongated support plate 80 similar to support bracket 82. The innermost planar side portion of support plate 80, as viewed in FIG. 4, frictionally slidingly contacts bracket 34 thereby maintaining support plate 8th in parallelism as it is pivotally swung about support shaft 81. Suitably mounted between elongated support brackct 82 and support plate dil is a transmission 93 which has the respective end port-ions bolted or otherwise secured to the respective bracket 82 and plate 8% to provide a unitary structure, so that the transmission is swingable with support bracket 82 upon actuation of hydraulic jack 92 to provide a clearance space in a manner to be described.

As shown in construction lines in FIG. 5 motor 97 is suitably journaled on bracket 82 on the side thereof opposite to which transmission 93 is connected. Motor 97 is the input to transmission 93, with transmission 93 having an output shaft to which is connected the sprocket 95 which sprocket 95 supports the endless cutter chain 6%. In order to limit the downward or extended movement of the arm ti t a stop block 83 may be located on the lower intermediate portion of support bracket 82 abuttingly engaging the intermediate bottom edge portion of lever arm 34 when lever arm 84 is in its fully extended position as shown in FIG. 5 and wherein the support bracket 32 is also shown in its fully extended position. Thus movement of the lever arm 84 and disk 86' by hydraulic jack 92 is resisted from further downward or extended movement by the block 83 and thereby also relieving the strain on the pivot shafts 85 and 87 which was imparted to them by the force of the jack 92 during its actuation to extend the cutting head 10 to its extended operative position.

In operation, the mining machine is brought to the working mine face with the scraper blade head 26 retracted upwardly in a manner well known in the art and each auxiliary cutting head It} with support plate 80 and support bracket 82 folded or swung inwardly in inoperative position. The scraper blade head is lowered into working engagement with the ground surface and the cutting heads 10 are then swung by the hydraulic jacks 92 respectively to position the auxiliary cutting heads 10 4 into extended working position. As fluid pressure is admitted to the cylinder end of each hydraulic jack 92 and the rod end thereof being connected to exhaust, the triangular shaped disk 86 (FIG. 5) is rotated counterclockwise about shaft 88, swinging shaft 87 similarly in a counterclockwise direction which thereby moves lever arm member 84 downwardly thereby swinging support bracket 82 in a counterclockwise direction about pivot shaft 81 with the arcuate slot 90 on support bracket 82 slidingly contacting stationary shaft 88 until the uppermost end of arcuate slot 99 comes to rest or into abutting engagement with the stationary shaft 88 thereby limiting the downward movement of the support bracket 82. With the cutting head 10 in its extended working position the axial center of shaft 87 with its connection to the disk 86 is located below a straight line connecting the axial centers of shafts 85 and 88. Thereby, since the pivot shaft 87 is below the line connecting the shafts 85 and 88 as mentioned above, the support bracket 82 is maintained in extended position without any downward influence by the jack 92. It should be noted that any movement, if it were possible to do so, of the bracket 82 and likewise the shaft 85 in an upward direction would, Without also a retraction movement of the disk 86 and the jack 92, urge the location of the pivot shaft 87 further downward below the straight line connecting the centers of shafts 85 and 88 because the center of shaft 85 swings on an arc struck from the axis of support shaft 81 and the shaft 87 swings on an arc struck from the axis of shaft 88. In the extended working position of the cutting head It), upward movement of the head 10 is resisted by the overall weight of the head 10 and its associated parts. The mounting of the transmission 93 and motor 97 on the head 10 provides a positive drive for the cutter chain 60 and the arrangement of the associated parts which are actuated to extend and retract the cutting head into and out of working position and maintains the cutting head in extended working position provides for an exceptionally efiicien t cutting head. Conversely, retraction of the hydraulic jack 92 first swings disk 86 about pivot shaft 88 in a clockwise direction thereby swinging pivot shaft 87 similarly in a clockwise direction from its location below the aforementioned line to a location coincident with or slightly thereabove which upon further retraction of the jack 92 to move the disk 86 in a further clockwise direction exerts a lifting force to lever arm 84 and the bracket 82 and causes retraction of the cutting head 10 into its retracted position. 7

Having described a preferred embodiment of this in-' vention in accordance with the patent statutes, it is to be realized that modifications thereof may be made without departing from the spirit of this invention. Accordingly it is respectfully requested that this invention be interpreted as broadly as possible and be limited only by the appendant claims. I. What is claimed is: 1. In a mining machine having a cutter sprocket support pivotably mounted on a frame defining a first pivot axis, said support having an arcuate slot centrally therein, said slot having an upper end portion and a lower end portion, means on said frame selectively engaging said end portions of said slot limiting the pivotal movement of said support, said means engaging said upper end portion upon movement of said support into extended operative position thereby locating said support in said position, a first link pivotally mounted on said means being connected to a power operated jack, a second link having end portions respectively pivotally connected to said support and said first link wherein said pivotal connection between said second link and said first link lies below a line connecting said first link pivot connection to said means with said second link pivot connection to said support.

2. In a mining machine as set forth in claim 1 wherein said support has auxiliary guide means slidably engaging said frame for guiding and supporting said support.

3. In a mining machine having a mobile frame and a cutter head mounted on the forward portion of said frame for cutting in advance of the machine, said frame having a laterally extending sprocket support adapted to guide a trimmer chain, said sprocket support being pivotally mounted on said frame about an axis substantially parallel to the longitudinal center line of the machine, said support having a transmission and guide means mounted therewith, said guide means cooperative with said frame for supporting and guiding said transmission and said sprocket support, a pivot shaft located on said frame and projecting outwardly through an arouate slot on said support for locating and supporting said support in a first position which is a laterally extended position, toggle linkage means connected to said support and said frame for holding said support in said first position, said toggle linkage means comprising a pair of links having adjacent ends pivotally connected together with one of said links pivotally connected to said support and the other of said links pivotally connected to said pivot shaft, power operated means mounted on said frame pivotally connected to said other link for moving said support into said first position and into a second position 10 which is a retracted position.

References Cited in the file of this patent UNITED STATES PATENTS Robbins Apr. 5, 1955 Evans et a1. Oct. 2, 1956 Silks a June 9, 1959 

1. IN A MINING MACHINE HAVING A CUTTER SPROCKET SUPPORT PIVOTABLY MOUNTED ON A FRAME DEFINING A FIRST PIVOT AXIS, SAID SUPPORT HAVING AN ARCUATE SLOT CONTRALLY THEREIN, SAID SLOT HAVING AN UPPER END PORTION AND A LOWER END PORTION, MEANS ON SAID FRAME SELECTIVELY ENGAGING SAID END PORTIONS OF SAID SLOT LIMITING THE PIVOTAL MOVEMENT OF SAID SUPPORT, SAID MEANS ENGAGING SAID UPPER END PORTION UPON MOVEMENT OF SAID SUPPORT INTO EXTENDED OPERATIVE POSITION THEREBY LOCATING SAID SUPPORT IN SAID POSITION, A FIRST LINK PIVOTALLY MOUNTED ON SAID MEANS BEING CONNECTED TO A POWER OPERATED JACK, A SECOND LINK HAVING END PORTIONS RESPECTIVELY PIVOTALLY CONNECTED TO SAID SUPPORT AND SAID FIRST LINK WHEREIN SAID PIVOTAL CONNECTION BETWEEN SAID SECOND LINK AND SAID FIRST LINK LIES BELOW A LINE CONNECTING SAID FIRST LINK PIVOT CONNECTION TO SAID MEANS WITH SAID SECOND LINK PIVOT CONNECTION TO SAID SUPPORT. 